Patent Document 1 below describes a vehicle seat wherein an impact pressure bearing frame is disposed to the front of a seatback frame, and a lower end portion of the impact pressure bearing frame is fixed to the seatback frame. A headrest support frame that supports a headrest is joined to an upper end portion of the impact pressure bearing frame, and the headrest support frame is supported on the seatback frame through a turning member such that the headrest support frame is capable of turning.
In the event of a vehicle rear collision, the headrest is moved (displaced) towards the front (what is known as an “active headrest”). The occupant is suppressed from sustaining whiplash injury due to the headrest restraining the head of the occupant.
Note that in the event of a vehicle rear collision, it is desirable for the head of the occupant that is moving towards the vehicle rear under inertia to be promptly restrained by the headrest.
Patent Document 1: Japanese Utility Model Application Laid-Open (JP-U) No. H07-001842